1. Field of the Invention
The present invention relates to a protective cap that protects a sprinkler head for extinguishing fire from external shock and dirt and to a sprinkler head provided with the protective cap.
2. Description of the Related Art
Sprinkler heads are disposed on ceiling surfaces and wall surfaces inside buildings. A sprinkler head includes, on one end side thereof, a nozzle that can be connected to a pipe installed inside a space above the ceiling or inside a wall and is provided with a thermally responsive unit on the other end side. During normal times, the thermally responsive unit supports a valve body that closes the nozzle.
An example of the above-described sprinkler head is illustrated in FIGS. 11 and 12 of International Publication Pamphlet No. WO 2011/125921. A sprinkler head SH illustrated in FIG. 7 of the present application is mostly disposed inside a space above a ceiling and, on the front side of the ceiling, a lower end of the sprinkler head, that is, a deflector D, is disposed in a projecting manner.
During installation work of the sprinkler head SH, a leak inspection is carried out after connecting the sprinkler head SH to a pipe P laid in the space above the ceiling. From after the completion of the leak inspection until the installation work of the ceiling boards is completed, a protective cap C is mounted on the sprinkler head SH. The protective cap C is for protecting the sprinkler head SH from external shock while the sprinkler head SH is stored, transferred, and while the installation work is carried out, and is for preventing adhesion of paint and foreign matters such as dust during the installation work.
A drain hole E is provided in a base of the protective cap C so that leakage of water can be checked during the leak inspection. The sprinkler head SH illustrated in FIG. 7 is configured so that the deflector D is disposed so as to be exposed to the outside of the body and so that the underside of the deflector D is adjacent to the base of the protective cap C while the protective cap C is in a mounted state.
If the is any leakage from a gap between the pipe P and a screw T or from a nozzle (not shown) inside the screw T, the water that has leaked out flows to the base of the protective cap C and is discharged from the drain hole E. However, due to the gap between the base of the protective cap C and the underside of the deflector D, surface tension of water is created that causes the water to disadvantageously take a considerable amount of time to be discharged from the drain hole E. As such, there is a concern of overlooking the sprinkler head in which a leakage has occurred because of water not being discharged within the inspection time.